Hinged derail with assisted manual lifting and method for constructing

ABSTRACT

This invention relates to hinged derail assemblies used in the railroad industry as a safety device for derailing a wheel of an undesirably moving railed vehicle, such as a railroad freight car. The hinged derail assembly includes a base that is rigidly mounted on a pair of spaced railroad ties and is operatively positioned adjacent one rail of a pair of conventional railroad rails. A derail shoe is pivotally mounted on the derail base and is moveable between an operative or derailing position and an inoperative position when the derail shoe is moved away from the rail. When the derail shoe is on the rail, a deflecting member on the shoe is positioned to angularly deflect a wheel of the freight car or the like which is undesirably rolling along the rail. This causes the derailing of the wheeled vehicle and prevents harm to things or personnel in the area. In the present invention a biasing member, such as a torsion spring, is operatively secured to both the base of the hinged derail assembly and the derail shoe itself. The spring provides upward rotational force both when the derail shoe is in the inoperative position and in the operative position. This lifting force provides assistance to a worker in the manual lifting of the heavy derail shoe between both the operative and inoperative positions. The invention also relates to a method of constructing the hinged derail wherein the torsion spring is installed when the derail shoe is in a substantially upright position and when the spring is unstressed. In this way, the spring is in a stressed condition, that is, either in a wound condition or in an unwound position, to provide a lifting force for the operator whether the derail shoe is in the operative position or in the inoperative position.

BACKGROUND OF THE INVENTION

This invention relates generally to safety equipment, namely, derails,which are commonly used for derailing railed vehicles, particularlypowered and non-powered railroad cars such as box cars, flat bedrailroad cars and the like, which are undesirably moving along railroadtracks. More specifically, the invention relates to hinged derails whichmay be selectively positioned adjacent one of a pair of railroad tracksfor movement between an operating position for engaging and derailing awheel of an undesirably moving railroad car and an inoperative positionfor allowing a moving railroad car to pass by the derail withoutundesirably engaging and derailing the moving railroad car. Thisinvention also relates to a method for constructing the hinged derail ofthe invention.

Derails of various types have been used for many years in the railroadindustry, some derails being in excess of one hundred years old. Derailsare commonly used as safety devices to prevent or limit unintended orundesired movement of a railroad car, such as a box car. Derails havebeen used extensively, such as along side rails adjacent to a main linetrack for railroad trains and in railroad yards where railroad cars areconstantly being moved, such as between coupled positions and uncoupledpositions. Typical derails are configured to be manually orautomatically moveable between a retracted or inoperative position inwhich a deflecting block is disposed adjacent but away from a rail forallowing free movement of a railroad car past the derail andalternatively, at a deployed or operative position in which thedeflecting block is positioned on top of and aligned with one of aconventional pair of railroad tracks for engaging and deflecting anoncoming wheel of an undesirably moving railroad car off the track.These derails cause the one wheel to be deflected and thereby the car tobe deflected to a stopped, non-moving position so as to avoid injury toother equipment or to personnel.

Generally speaking, hinged derails include a deflecting block rigidlymounted on a derail shoe. The derail shoe is pivotal about a pivot axis,mounted on a base secured to a pair of railroad ties. Examples of suchhinged derails may be seen, for example, in Hayes U.S. Pat. No. 988,190;Hayes U.S. Pat. No. 1,464,607; Hayes U.S. Pat. No. 1,627,092; Hayes U.S.Pat. No. 1,702,083; Hayes U.S. Pat. No. 2,430,567; Hayes U.S. Pat. No.3,517,186; and Pease U.S. Pat. No. 6,178,893 B1.

In the operation of hinged derails, a derail shoe is pivoted between theretracted or inoperative position, which is spaced away from therailroad rail, and a deployed position or operative position where thedeflecting block of the derail shoe is aligned generally on top of therail. Proper alignment requires both lateral alignment and verticalalignment to a location on top of the rail with the deflecting blockpositioned to engage the leading wheel of an undesirably moving railroadcar. The base of the derail is generally affixed to a pair of adjacentrailroad ties of the type commonly used in the railroad industry, withattachment being accomplished generally by spikes driven throughopenings in the base into the ties. The base is mounted on the ties, inthe area between a pair of rails in a position operatively adjacent toone of the rails.

Once the derail is in position, that is, affixed to the railroad ties,the installed derail is in a substantially permanent position. Thederails are made of solid steel and are very heavy as they must derail aheavy, moving rail car. The pivoted derail shoe itself may weigh in therange of 80-120 pounds. Clearly, the heavy derail shoes are not easilymanually rotated between operative and inoperative positions. In theinoperative position, the derail shoe, being pivotally mounted to thederail base, is deployed away from the adjacent rail in a substantiallyaligned position on the base in a position with the derail block facingdownwardly and away from the rail so as to allow a moving railroad carto pass without being derailed. When desired, the railroad worker mustmanually lift the pivoted derail shoe in an upward circular motion andthen rotate it downwardly into position with the deflecting block on therail so the deflecting block will be in a position for engaging thewheel of a railroad car which is moving in an undesired manner. Thismeans that the railroad worker must physically bend down and manuallyand rotatably lift the derail shoe about the pivot axis of theattachment to the base and move the derail shoe to the operativeposition on the rail. This action is physically difficult and can causephysical injury, such as to the back of the railroad worker. Similarly,when the derail shoe with the deflecting block is moved by the worker inthe opposite direction, that is, from the deflecting or operativeposition to the inoperative position, the same problem occurs, that isthe heavy derail shoe must be movably lifted and rotated in the oppositedirection to the inoperative position. Again, the operator risks or mayeven encounter serious injury such as to the back.

Thus, there is a clear need for a hinged derail that significantlyreduces the stress placed on an operator's back in rotationally movingthe derail shoe both from the inoperative position to the operativeposition on the rail and from the operative position to the inoperativeposition. In addition, there is a need to provide forcible liftingassistance to the required manual lifting of the derail shoe withoutusing expensive parts, and without adding weight to the already heavyderail shoe. Finally, there is a need to provide a method forconstructing the hinged derail of this invention in an efficient andeconomical manner.

SUMMARY OF THE INVENTION

The above mentioned need for assistance in manually moving the derailshoe both from the inoperative position to the operative position andfrom the operative position to the inoperative position is accomplishedby providing a biasing member on both the derail base and the derailshoe wherein the biasing member provides lifting assistance to themanual lifting of the shoe when the shoe is in both the operativeposition and the inoperative position. Preferably, a torsion spring isphysically positioned around a pivot shaft which is mounted on thederail base and on the derail shoe and which provides a pivot axis forthe derail shoe. One end of the torsion spring is secured to the baseand the other end of the torsion spring is affixed to the derail shoe.More preferably, the design of the torsion spring is such that itprovides lifting force for assistance to the worker to relieve stress onthe worker when the derail shoe is lifted and rotated. This isaccomplished by designing the torsion spring to be in a stressedcondition, that is, in a wound condition or in an unwound condition,where the derail shoe is in the full operative position or in the fullinoperative position. In one embodiment, where the derail shoe isrelatively light in weight, the torsion spring is in a stressed, unwoundcondition when the derail shoe is positioned on the rail and is in astressed, wound condition when the derail shoe is in the operative,off-rail position. In another embodiment, when the derail shoe isrelatively heavy in weight, the torsion spring is in a stressed, unwoundcondition when the derail shoe is in the inoperative, off rail positionand is in a stressed, wound condition when the derail shoe is in theoperative, on rail position. The spring is designed to be in asubstantially relaxed position when in a generally upright position. Theoperator thereby has the benefit of the lifting force of the torsionspring both when the spring is in the stressed, wound position and inthe stressed, unwound position with the spring being substantiallyrelaxed or unstressed in the upright position. The use of the torsionspring adds no weight to the pivoted derail shoe, requires no externalassistance such as from a powerized source, and is of economical design.The method for manufacturing the hinged derail with the torsion springenables the spring to provide the desired lifting force for assistingthe worker when the derail is in both the operative position and in theinoperative position.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are incorporated into and form part of thedescription of the invention. The drawings illustrate certainembodiments of the present invention and, together with the detaileddescription of the invention provided below, serve to explain anddescribe one preferred embodiment of the invention. The drawings are notto be construed as limiting the scope of the invention but are intendedto assist in fully describing the invention.

Referring to the drawings:

FIG. 1 is a perspective view of a railroad worker moving the derail shoeof the derail, made in accordance with the invention, from theinoperative position to the operative position on top of a railroadrail;

FIG. 2 is perspective view of the derail of FIG. 1 with the derail shoeof the invention being positioned with the deflecting block positionedfor engaging the wheel of an undesirably moving railroad car;

FIG. 3 is a perspective view, similar to FIG. 2, showing the derail shoeof the present invention being in the inoperative position with thedeflecting block spaced away from the top of the rail;

FIG. 4 is a top plan view of the derail of the present invention withthe derail shoe being in the operative position on top of the railroadrail;

FIG. 5 is an end elevational view of the derail shown in FIG. 4, asviewed from the pivot end of the derail;

FIG. 6 is a side elevational view of the derail of FIGS. 4 and 5 withthe derail shoe being in an operative position on top;

FIG. 7 is a sectional view of the derail as viewed along line 7-7 ofFIG. 5, showing the derail mounted on a rail; and

FIG. 8 is an illustrative drawing showing the derail shoe, in solidlines, when the torsion spring is in a substantially relaxed conditionwithout biasing the derail shoe in either direction and also showing, indotted lines, the positions of the derail shoe in both the inoperativeposition and in the operative position.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 2, the derail assembly, generally 20, of the presentinvention is shown in the operative or derailing position, as will bedescribed in more detail hereinafter. The derail assembly 20 includes aderail base, generally 22, which pivotally carries a derail shoe,generally 24. FIGS. 1-3 illustrate a pair of spaced railroad ties 26 ofconventional construction, usually of wood or other material which canbe penetrated by conventional railroad spikes. As shown in FIGS. 1-3, asection of a railroad rail, generally 28, in a conventional manner restsupon the outer portions of the railroad ties 26, transversely thereto.The rail 28 is of conventional steel construction and includes a lowerrail flange 30 which rests upon the upper portion of the railroad ties26, an upper rail flange 32 and a generally upright web 34 whichunitarily interconnects the lower rail flange 30 with the upper railflange 32.

Referring to FIG. 2, the derail assembly 20 is shown in the operativeposition. The derail assembly 20 is shown in the inoperative position inFIG. 3. In the operative position, the derail shoe 24 is operativelypositioned on the upper surface of the upper flange 32 of the rail 28.Referring to FIG. 3, the derail shoe 24 of the derail 20 is pivotallymounted about a pivot shaft 36 which is spaced laterally inwardly fromthe rail 28 and is rigidly mounted on the derail base 22, as will bedescribed hereinafter in greater detail.

A torsion spring member, generally 38, as seen in pictorial view in bothFIGS. 2 and 3 provides upward biasing or lifting assistance to theoperator when the operator manually lifts the derail shoe 24, when thederail shoe 24 is both in the inoperative position of FIG. 3, and in theoperative position of FIG. 2. Specifically, the torsion spring 38 isdesigned to be in a stressed condition, that is, in the wound or unwoundconditions when the derail 20 is in either the operative position (FIG.2) or the inoperative position (FIG. 3).

Referring to FIGS. 2-6, the derail base 22 of the present invention isgenerally of welded steel construction. The derail base 22 includes apair of spaced horizontal plates 40, each of which rests upon the uppersurface of each of the spaced railroad ties 26. The horizontal plates 40include multiple apertures 43, as seen in hidden view in FIG. 5, forallowing the passage of multiple railroad spikes 42 which are driveninto the spaced railroad ties 26, in a conventional manner to secure theassembly 20 in place on the ties 26. The inner facing edges of thehorizontal plates 40 each have upright, rigid support flanges 44 mountedthereon, as by welding. The outer faces of the flanges 44 projecttowards and bear against the inner facing edges of the railroad ties 26and provide added positioning support for preventing rotational andtransverse movement of the derail base 22 and the derail assembly 20when positioned on the ties 26 and adjacent the rail 28. The uprightflanges 44 each include a unitary projection 46, having upwardly angledlower portions, which project towards the rail 28. An angled crosssupport 48 is rigidly welded to the under portions of the projections 46of the upright flanges 44. The angled cross support 48 extends for theentire width of the derail base 22 and is positioned against the upperface of the lower flange 30 of the rail 28. The angled support 48 isalso welded to the inner facing edges of the horizontal plates 40 of thederail base 22.

A rigid support rod 50 is welded to the outermost portions of theupright flanges 44. The support rod 50 provides added rigidstrengthening for the derail base 22. Preferably, the support rod 50 isin general alignment with the horizontal plates 40. In order to providefurther support for the base 22, a pair of support blocks 52 are weldedto the upper surface of each horizontal plate 40 and to the outer faceof each of the upright flanges 44. Each block 52 is rigidly positionedjust below the pivot shaft 36. In summary, the derail base 22 is ofheavy duty, rigid, construction and design accomplished by the spacedhorizontal plates 40, the upright flanges 44, the angled flange 48, andthe support rod 50. The derail assembly 20 is securely positionedagainst the rail 28 once the spikes 42 are driven through the apertures41 provided in the horizontal plates 40.

Referring to the perspective views FIGS. 2 and 3, the pivotal derailshoe 24, like the base 22, is of welded steel construction. The derailshoe 24 includes a horizontal deflecting plate 54 which is designed torest upon the upper surface of the upper flange 32 of the rail 28 whenin the operative, derailing position, as seen in FIG. 2. Specifically,the lower surface of the deflecting plate 54, when in the operativeposition, bears against the upper rail flange 32. A deflecting bar 56 ismounted by welding onto the upper surface 58 of the deflecting plate 54,as seen when the derail shoe is in the operative position of FIG. 2.

As seen in FIG. 4, the deflecting bar 56 is angled, as in a range of 11degrees to 28 degrees from left to right, along and relative to thecenter line of the upper surface of the upper rail flange 32. When arail car is undesirably moving along the rail 28, a wheel (not shown) ofa railroad car (not shown) will be deflected off the rail 28. Thisderailing action thereby derails and stops the undesired movement of thecar. It is to be understood that such deflecting bars may also be angledin the opposition direction, that is, in case of movement of a railcarin the opposite direction, as from right to left in FIG. 2. Furthermore,double ended derails, such as seen in U.S. Pat. No. 6,202,564, aredesigned to deflect a runaway rail car moving in either direction alonga set of rails. An added support block 60 is welded to the deflectingplate 54 and abutting against the deflecting bar 56 to provide addedrigidifying support for maintaining the angled position of thedeflecting bar 56 on the upper surface of the rail 28, as the wheel ofan undesirably moving heavy rail car strikes the deflecting plate 54 andthe angled deflecting bar 56.

A pair of spaced upright side plates 62 are rigidly mounted, as bywelding on the under surface of the deflecting plate 54, as viewed whenthe deflecting plate 54 is in the position of FIG. 2. The laterallyspaced side plates 62 are rigidly interconnected by a front cross brace64 and a spaced rear cross brace 66, as viewed in FIG. 2. The frontbrace 64 and the rear brace 66 are each interconnected, by welding, tothe inner faces of the spaced side plates 62. Another cross supportbrace 69 is welded to the top edges of the side plates, as viewed inFIG. 3. The side plates 62 and thereby the entire derail shoe 24, arepivotally carried on the pivot shaft 36 which is rigidly mounted on thebase 22. The pivot shaft 36 is secured, as by welding, at its oppositeends to the flanges 44. The torsion spring 38 is mounted on the shaft 36at the time of construction.

The provision of the torsion spring 38 on the pivot shaft 36, asdescribed herein, provides the desired assistance to manual lifting ofthe derail shoe 24. One problem with prior manually operated hingedderails is that the manual lifting of the heavy derail shoe 24 can causeinjury, particularly back injuries to the worker. Generally, priorderail shoes 24 of the type used in the railroad industry may weigh80-120 pounds. The present derail 20 provides a convenient lift handle68 for the operator to more easily grip the shoe 24. The handle 68 isfixed to the central outer portion of the deflecting plate 54 of thederail shoe 24. The operator must manually lift and pivot the derailshoe 24 upwardly between both the operative and inoperative positions ofFIG. 2 and FIG. 3 respectively. The derail shoe 24 is the heaviest whenit is completely on the rail, that is in the operative position, or offrail, that is, in the inoperative position. The weight of the shoe 24 isconcentrated at its center of gravity which is horizontally farthestaway from the pivot axis 36 when the shoe 24 is in the operative andinoperative positions.

During construction of the derail assembly 20, the torsion shaft 36 ispassed through the spring 38. The shaft 36 thereby passes through thetorsion spring 38 and also passes through the apertures provided in theupright support plates 62 and flanges 44. The outer ends of the shaft 36are then securely mounted by welding in the openings provided in theupright flanges of the base 22. As seen best in FIGS. 6, 7 and 8, onesubstantially straight projecting end 67 of the torsion spring 38 ispositioned in an aperture 70 on the near cross brace 66 of the derailshoe 24. As seen in FIGS. 4, 5, 7 and 8, a cylindrical support member 72is rigidly secured, as by welding, to the support rod 50 of the derailbase 22. The support member 72 faces angularly upwardly and inwardly andincludes a central aperture 74 which receives the opposite substantiallystraight projecting end 76 of the torsion spring 38. The spring 38 isthereby operatively secured at both ends 67 and 76 to the derail base 22and to the pivoted derail base 24.

The torsion spring 38 is installed on the pivot shaft 36, when thepivoted derail shoe 24 is in the generally upright position, as shown inFIG. 8, when the center of gravity of the shoe is substantially directlyabove the pivot shaft 36. At this rotated position, the derail shoe 24can be readily held in this generally upright position which is theapproximate balance point of the shoe 24 pivotally carried on the base22. The torsion spring 38 is passed around the pivot shaft 36. Aspreviously described, the pivot shaft 36 is then passed through theopenings in the upright flanges 44 of the derail shoe 24. The pivotshaft 36 is rigidly secured, as by welding, within the openings providedin the derail base 22. The shoe 24 is then pivotal relative to the base22.

In further explanation, the torsion spring 38 is installed when in thesolid line position of the upright derail shoe 24 shown in FIG. 8. Thespring 38 is in an unstressed condition, because the center of gravityof the shoe is above the pivot axis of the shaft 36. When the shoe ispivoted to the inoperative position (FIG. 3) or to the operativeposition (FIG. 2), the spring 38 is in the wound or unwound position,that is, the spring is stressed. The torsion spring 38 tends to returnto its unstressed condition when in either position. However, the weightof the derail shoe 24 is designed so as to not allow the spring 38 tomove the shoe up to an unstressed condition. The stressed spring 38thereby exerts a lift force against the derail shoe 24 in both positionsbut the torsion spring 38 and the weight of the shoe 24 are coopertivelydesigned to keep the shoe down in both the operative and inoperativepositions.

In the drawings, a lighter weight derail, as about 95 pounds, is shownand the torsion spring 38 is in a wound, stressed condition when theblock or shoe 24 is on the rail 28 as seen in FIG. 2 and is in anunwound, stressed condition when the spring 38 is in the off the railposition of FIG. 3. As most preferred, when the derail shoe 24 is on therail 28 the weight of the shoe 24, such as about 95 pounds, overpowersthe lift force of the stressed, unwound spring and the effort to liftthe shoe 24 with the handle 68 is only approximately 15-20 pounds.Without the spring 38, the lift force would be at least 30-50 pounds. Asthe block 24 is further rotated to the off rail position, the spring 38winds to the stressed, wound condition, increasing its potential energy.The weight of the block 24 overcomes the stressed spring. The liftingeffort of the derail shoe 24 from off rail to on rail is also in the15-20 pound range. In one embodiment, for example, when the weight ofthe shoe is lighter in weight and is approximately 95 pounds, thespecifications of the spring 38 are as follows:

Torsion Cylind Close Wound Chrome Vanadium Round Wire Dia (in) 0.3310Mean Dia (in) 1.5790 ± .032 Active Coils 11.2383 Rate (#-in/deg) 5.2195Inside Dia (in) 1.2480 Total Coils 11.2383 Spring Index C 4.7704 OutsideDia (in) 1.9100 Active Legs (in) 0.0000 Nat Preg (Hz) 94.9118 Min I.D.(in) 1.2081 Addl Feed (in) 0.0000 Body Length (in) 4.0509 Devel Lngth(in) 55.7482 Max Bdy Len (in) 4.1474 Weight (lbs) 1.3624 Free Point 1Point 2 Moment Arms (in) Force at Arm (lbs) Moment (#-in) Angle (deg)265.7702 Deflection (deg) UNK Stress (psi) UNK Stress % of MTS

The specifications for the spring 38, as would be apparent to oneskilled in the art, vary depending on the weight of the derail shoe 24.In another embodiment, for example, when the weight of a shoe is heavierin weight and is about 110 pounds, the specifications of the spring areas follow:

Torsion Cylind Close Wound Chrom Vanadium Round Wire Dia (in) 0.4060Mean Dia (in) 1.7300 + .032 Active Coils 13.2300 Rate (#-in/deg) 9.1600Inside Dia (in) 1.3240 Total Coils 13.2300 Spring Index C 4.2611 OutsideDia (in) 2.1360 Active Legs (in) 0.0000 Nat Preg (Hz) 82.3814 Min I.D.(in) 1.2867 Addl Feed (in) 0.0000 Body Length (in) 5.7774 Devel Lngth(in) 71.9045 Max Bdy Len (in) 5.8958 Weight (lbs) 2.6437 Free Point 1Point 2 Moment Arms (in) Force at Arm (lbs) Moment (#-in) Angle (deg)262.8000 Deflection (deg) UNK Stress (psi) UNK Stress % of MTS

More specifically, the method of manufacturing the derail assembly 20 isas follows relative to the assembly of the torsion spring 38 on theassembly 20 as described. The derail shoe 24 is inserted into the baseassembly 22. The pivot shaft 36 is passed through one side of thesupport flange 44 of the base 22 and then into the plate 62 of thederail shoe 24. At this time, the end 67 of the torsion spring 38 isinserted into the aperture 70 of the rear cross brace 66 of the shoe 24.The pivot shaft 36 is then passed in the same direction through thecenter of the torsion spring 38. The end 67 of the spring 38 ispositioned in the brace 66 and then the pivot shaft 38 is passed throughthe opposite side plate of the shoe 24. The pivot shaft 36 is lined upwith the aperture in the support flange 44 and the end of the pivotshaft 36 is inserted into the support flange 44. The pivot shaft 36 isthen welded at both ends to the support flange 44 of the base 22. Theaperture 74 of the cylindrical support member 72 is then slid over thestraight projecting end 76 at the torsion spring 38. The derail shoe 22is then pivoted upwardly approximately 65 degrees to a point where thederail shoe balances at its center of gravity relative to the pivotshaft 36. The spring 38 is unstressed when the derail shoe 24 isbalanced. The final method of assembly is to then secure, as by welding,the cylindrical support member 72 to the support rod 50 at the base 22.The spring 38, being unstressed in the upright, balanced condition ofthe derail shoe 24, comes into a stressed condition, that is, in a woundor unwound condition, when the shoe 24 is in either the operationalposition or the unwound position.

Referring again to FIG. 8, the dotted line views show the position ofthe derail block 24 in the operative position as well as in theinoperative position. As described and as shown in the drawings, thereis approximately a 65 degree angle from the horizontal when a relativelylight in weight derail shoe 24 is in the solid line position, that is,when the torsion spring is unstressed. Rotating the lighter derail shoeapproximately 65 degrees to the on rail position unwinds the spring 38and the spring 38 stores the strain energy for assisting in rotating thederail off the rail 28 when desired. In the opposite direction, which isfrom the 65 degree position of FIG. 8 to the hidden line, off railposition shown in FIG. 8, the lighter shoe 24 is approximately 105degrees from the horizontal. Moving the shoe 24 to the inoperativeposition of FIG. 8 causes the spring 38 to store the strain energy andwinds the spring. The strain energy thereby assists in rotating thelighter derail shoe to the on rail position of FIG. 2 from the off railposition of FIG. 3.

While in the foregoing there has been provided a detailed description ofa preferred embodiment of the present invention, it should be recognizedto those skilled in the art that the described embodiment may be alteredor amended without departing from the spirit and scope of the inventionas defined in the accompanying claims.

1. A hinged derail assembly for derailing a wheel of a wheeled railedvehicle, the derail assembly being mounted on and between two rail tiesand being selectively positioned adjacent one rail for accomplishingsaid derailing of undesired movement of the wheeled vehicle, said derailassembly comprising: a base rigidly secured to said rail ties; a derailshoe pivotally mounted on said base for manual movement between anoperative, derailing position and an inoperative position, said derailshoe having a derail member positioned on said rail when in theoperative position on said rail for deflecting said wheel from rollingon said rail and for thereby derailing said wheeled vehicle; and abiasing member operatively secured to both said base and said derailshoe for biasing said derail shoe in a substantially upward rotationaldirection for forcibly assisting in the manual lifting movement of saidderail shoe both from the inoperative position to the operativederailing position and from the operative derailing position to theinoperative position.
 2. The derail assembly of claim 1 wherein saidbiasing member is a spring member having a first end and a second end,means on said base for receiving said first end of said spring member,and means on said derail shoe for receiving said second end of saidbiasing member.
 3. The hinged derail assembly of claim 2 wherein saidspring member is a torsion spring, a rigid pivot shaft being mounted onsaid base, said spring member being mounted on said pivot shaft and saidderail shoe being pivotally mounted on said pivot shaft for pivotalmovement between the operative and inoperative positions.
 4. The derailassembly of claim 3 wherein said torsion spring is selectively in awound condition or an unwound condition when said derail assembly is insaid operative position or in said inoperative position.
 5. A method forconstructing a derail assembly for derailing a wheel of a wheeled railedvehicle, said derail assembly being of the type which includes a derailbase, a derail shoe pivotally mounted on said about a pivot shaft formanual movement between an operative position for derailing said wheeland an inoperative position, said method comprising the steps of:providing a biasing member having first and second ends for biasing saidderail shoe in a substantially upward rotational direction for forciblyassisting in the manual lifting movement of said derail shoe both fromsaid inoperative position to the said operative position and from thesaid operative position to the said inoperative position; providing arigid member for receiving said second end of said biasing member;positioning said biasing member on said pivot shaft; receiving saidfirst end of said biasing member on said derail shoe; pivoting saidderail shoe to a substantially upright and balanced condition relativeto pivot shaft and above said derail base while maintaining said biasingmember in an unstressed condition; securely positioning said second endof said biasing member on said rigid member while continuing to maintainsaid biasing member in an unstressed condition; and rigidly securingsaid rigid member to said derail base while continuing to maintain saidbiasing member in an unstressed condition which in said substantiallyupright and balanced condition.
 6. The method of claim 5 including thefurther step of positioning said derail shoe in the operative positionand simultaneously causing said biasing member to be in a stressedcondition to assist in the manual movement of said derail shoe from theoperative position to the inoperative position.
 7. The method of claim 5including the further step of positioning said derail shoe in theinoperative position and simultaneously causing said biasing member tobe in a stressed condition to assist in the manual movement of saidderail shoe from the inoperative position to the operative position. 8.The method of claim 5 including the step of providing a torsion springas the biasing member and positioning said torsion spring around saidpivot shaft.